The Wasteless Free-Form Formwork construction technology combines existing processes and materials in a new way to fabricate non-repetitive free-form cast-on-site concrete structures using re-usable and digitally-fabricated wax formwork. The approach enables highly accurate, complex and free-form geometries of contemporary architectural production to be fabricated at lower cost.

Project Timeline

December 30, 2013 | Project Update | Zurich, Switzerland

Matthias Kohler, Professor of Architecture & Digital Fabrication has taken over the leadership of a Swiss National Centre of Competence in Research. Matthias Kohler is project author of High-efficiency concrete formwork technology which won both a Holcim Awards Acknowledgement prize for Europe in 2011 and the inaugural global Holcim Innovation 1st prize in 2012.

The work of Matthias Kohler and his team and project partners on digital fabrication in architecture is now a National Centre of Competence in Research (NCCR) supported by the Swiss government. The magazine of the Swiss Federal Institute of Technology, ETH News, spoke to Matthias Kohler about why it is so important that novel design and fabrication processes evolve and that such a research approach does not remain purely theoretical. Research on digital fabrication in architecture is a relatively new area, but interest in it has grown substantially over the past few years. The fact that the political sphere and the government are now also supporting the issue at a national level opens up completely new research opportunities.

The NCCR Digital Fabrication will explore what a new digital building culture that meets the technological possibilities of the information age might look like. There are three areas of focus: the first area concerns the design and building processes. Nowadays, architects work almost exclusively on computers, but it is still unclear whether and how this affects the design and construction process itself. Here we are looking for new instruments to bring the design, planning and construction phases closer together in order to directly inter-relate them.

The second research area is almost obvious: anyone who wants to change the fundamental building culture needs new materials and construction processes. The third focus revolves around customized production. What happens if industrially manufactured parts can be individually manufactured? What happens if digitally controlled machines operate directly on a construction site? These three topics will be closely intertwined and examined on an interdisciplinary basis within this NCCR.

Field tests to construct full-scale building elements

The research team is constantly undergoing field tests, because their research on novel digital fabrication processes automatically takes place under real conditions. An important milestone in the project will be the construction of a full scale demonstrator after the first four years. New architecture and construction technologies can be tested at “Nest”, EMPA’s new building laboratory. The team will build a residential unit there, thus demonstrating the synthesis of the NCCR approach – learning most effectively by “making” – real physical implementation at full scale.

The research also seeks to progress building culture to become an innovative interplay between everyone involved in the design and construction process. This will also include a progressive change of the built environment and living environments of the next generation.

Collaboration with research institutes

The research project is a large collaboration with several research institutes. At ETH alone, scientists from the departments of architecture, IT, electrical engineering, mechanical engineering and process engineering, and civil, environmental and geomatic engineering are involved. All these disciplines have a different understanding of research. One of the key challenges will be to synthesize these approaches and arrive at innovative methods and results together.

August 30, 2012 | Innovation Jury Report | Zurich, Switzerland

The jury commended the project for its excellent level of research and practice-oriented experimentation. The proposed concrete production process developed by a research team in Architecture & Digital Fabrication at the Swiss Federal Institute of Technology (ETH Zurich) is an ingenious approach to casting concrete surfaces of highly complex geometrical definition. It advances an entirely new sequence of production phases. First, a robot arranges a pile of sand within formwork into a shape that corresponds to the lower profile of the desired geometrical form to be cast.

Then, liquid wax is poured over the “dune shape” of the sand. Once cooled, the wax negative form becomes one element of the actual formwork, finally into which concrete is poured to produce the desired element. After the process is completed, the wax negative form can be heated and made liquid, in order to be reused for the next casting process. The same obviously applies to the sand used to create the wax negative.

The outstanding merits of this innovative concrete production method are fourfold: First, it eliminates the need to use expensive and marginally-recyclable construction materials such as wood and steel sheet, while replacing the traditional materials for concrete formwork by wax. At the same time, it reduces formwork-related construction waste almost to zero. Second, it considerably cuts down the tremendous volume of manual labor necessary to produce highly complex concrete formwork because robots take-over the majority of the workload. Third, the relatively low cost of this formwork technology is a prerequisite for the economical production of geometrically complex precast concrete elements in small series. Fourth, there are virtually no limits regarding the three-dimensional shape of precast concrete elements with a hitherto unimaginable degree of accuracy.

Overall, this visionary formwork technology for geometrically complex concrete elements is a real quantum leap combining the utmost computer-aided manufacture (CAM) technologies with the latest generation of robots that has the potential for revolutionizing the construction process enhancing sustainable construction.

Handover of the Global Holcim Innovation 1st prize for "High-efficiency concrete formwork technology", Zurich, Switzerland: Hans-Rudolf Schalcher, member of the Global Holcim Innovation prize jury and member of the Board of the Holcim Foundation.

The inaugural Holcim Innovation 1st prize was presented to Fabio Gramazio and Matthias Kohler, Professors of Architecture and Digital Fabrication at the Swiss Federal Institute of Technology (ETH Zurich) for their High-efficiency concrete formwork technology. In a team with Silvan Oesterle, Amar Mirjan and Axel Vansteenkiste, they have developed a technique for the production of unique free-form concrete components. The research focuses on new strategies for the production of contemporary architectural components and also the interplay between architectural design and new digital fabrication techniques.

The approach uses re-usable and digitally-fabricated wax formwork. The re-usable wax formwork is recyclable and saves material and energy compared to milling expanded polystyrene blocks for single-use applications, or using flexed sheets of material such as plywood which are limited to low curvatures.

The Holcim Innovation prize is a special accolade within the framework of the Holcim Awards competition, which attracted some 6,000 project submissions from 126 countries, recognizes innovative building materials and construction technologies in the context of sustainable construction.

Chairman of the Holcim Innovation prize jury, renowned architect and Professor of Architecture at the Swiss Federal Institute of Technology (EPFL) in Lausanne, Harry Gugger considers the High-efficiency concrete formwork technology approach to be a quantum leap. “To date, the production of complex concrete molds has been difficult to manufacture and has also produced a large volume of waste, but this approach solves both problems,” he said.

Emeritus Professor of Planning and Management in Construction at the ETH Zurich, and member of the Holcim Innovation prize jury, Hans-Rudolf Schalcher identifies significant market potential for the processes due to its obvious contribution to sustainability.

The prize of USD 75,000 was presented at the 18th Holcim Concrete Conference by Member of the Executive Committee of Holcim for Europe, Roland Köhler. The conference hosted at ETH Zurich on the theme of “Concrete: the building material for demanding buildings” was led by Prof. Thomas Vogel, Chair of Structural Engineering – Structural Design and Existing Structures at the Institute for Structural Engineering, ETH Zurich. Some 200 experts discussed the latest technology and systems including textile-reinforced shotcrete and technology transfer in construction. Case studies included the Swiss Prime Tower in Zurich, the Centro Commerciale in Chiasso, and the NEST research building in Dübendorf near Zurich.

The Holcim Innovation 1st prize 2012 went to Gramazio & Kohler, Architektur und Digitale Fabrikation at the Swiss Federal Institute of Technology (ETH Zurich), for a construction technology using molds that combine existing processes and materials in a new way to fabricate cast-on-site concrete structures with reusable and digitally-fabricated wax formwork.

Global Holcim Innovation prizes of USD 150,000 in total were allocated by a separate jury and conferred for the first time. These prizes focus upon contributions to innovative building materials and construction technologies in the context of sustainable construction. This additional recognition of projects submitted in the Holcim Awards reflects the increasing emphasis on driving and fostering innovative new solutions by Holcim, the sponsor of the competition.

Alexander Biner, Partner at MS Management Service AG, Switzerland, and member of the Management Board of the Holcim Foundation (left) and Marta Malé, Institute for Advanced Architecture of Catalonia (IAAC), Spain; Architectural Association (AA), UK; and member of the Holcim Awards 2011 Europe jury – presentation of Acknowledgement prizes.

At the regional ceremony of the Holcim Awards 2011 for Europe, a total of USD 300,000 was presented to ten outstanding projects submitted by architects, planners, engineers and project owners. The winning projects show the wide range of approaches in the region to sustainable construction that respond both to intensified urbanization and innovation in building materials and construction techniques.

The Wasteless Free-Form Formwork construction technology combines existing processes and materials in a new way to fabricate non-repetitive free-form cast-on-site concrete structures using re-usable and digitally-fabricated wax formwork. The re-usable wax formwork saves material and energy compared to milling expanded polystyrene blocks for single-use applications or using flexed sheets of material such as plywood which are limited to low curvatures.

A robotically-formed sand mold is created forming a re-meltable wax negative which is placed on-site as concrete formwork. The process can be complemented through computer-aided manufacturing that improves the creation of complex shapes of aesthetically sophisticated applications.

The technology enables complex and free-form geometries of contemporary architectural production to be fabricated using designs that are highly optimized in terms of material consumption, energy efficiency, and usability.